Molding device



M. T. DAVID MOLDING DEVICE May 2, 1950 Filed May 5, 1948 Patented May 2, 1950 UNITED STATES PATENT OFFIQ'E.

MOLDING DEVICE Marie 1 David, Los; Angeles, Calif. A pugatiofl May 194s;,,Seria1 Ne.'24,75 s

5'Claims. it l-he present invention relates to angimproved molding device useful, for example; and notas' a limitation; by dentists andlaboratory-technicians inmolding or casting operations.

An object of the present invention is to provide an improved device useful in molding operations characterized by the ease in Which it may be opera-ted to produce relatively large necessary pressures.

Another object of; the present invention is to provide an improved molding device having a trigger element which may be easily moved by the; use of'a personsfinger againstthe action of spring means which is subsequently effective to move an element-ate relativelylarge speed in the development of instantaneous high pressures.

' Stillanother object-of the present invention is to provide an improved molding device characterized by the incorporation therein of a novel tripping mechanism actuatable by a persons finger.

Yet a further object of the present invention ls'to provide an improved molding device having a plurality of tension springs; each being fully effective in moving an element to produce relatively large pressures from a cooked position but incorporating a novel finger-operated tripping mechanismwhich includes a tripping or searelement normally held in locked position by-onlyone ofsuch plurality of springs, so thata minimum amount of finger pressure is required to release the energy stored in the plurality of springs to allow suchmember-tomove under the influence of such plurality ofsprings.

The features of the present invention which are believed to be novel are set forth with particularity-in theappendedclaims. This invention itself, both as to itsorganization and manner of operation, together with further objects and advantages thereof, may be best understood by refei'ence to the following description taken in connectiqn with the accompanying drawings in whi h:

Figure lis a view insideelevation of, the novel molding device embodying the present: invention.

Figure 2 is a viewof the molding deviceshown iiiur 1 b t mhi wem m e l mostn si ion.

Figured is a topv plan; view of. the a paratus shown in Figure-,2;

Figure 4. is a. sectional. view taken. substantially onthelineal- 420f. Eiguram I Eligure 5 rise perspective-view atone eithe pies? .teacun. holding elements sh wn. in. Eigure'. 6

Figure 61s a sectional view taken substantially on the line B-6 of Figure 2.

Figure '7 is a sectional view similar-to thesectional view shown in Figure 1 but with the parts in: a different operating condition.

The device includes a stationary base member Iii arranged to hold a mold II, a spring-biased cap member l2 pivotally mounted with respect to said base member and. movable from 1125's cocked position shown in Figure 1 to its other extreme position shownin Figure 2 upon operation as the pivotally mounted finger-operated trigger member E3, the member ISbeing effective; as described in greater details below, to release the cooking mechanism whereby the tension springs l4, [5 are fully. effective to move the cap member l2 con,- taining the wet asbestos or Moldene" material it into engagement with theupper rim IE8 of the mold l I to thereby forceably eject preheated molding materials, such as gold 20, through the channel 21 into the preformed cavity. 22 ofpredetermined configuration. The mold: ll per" se is of conventional structure and made in accord;- ance with conventional means and comprises a cylindrical plaster body encased within the sheet metal retaining member 23, which, inturn, ism,- siliently. mounted with respect to the basemember; H1 by ag-pair of diametrically and oppositely disposed spring-urged contacting members 24, 25 each. one of these contact members 24,15 being of identical arcuate shape and having afiixed' theretoa guide rod 26, 21, respectively, passing through corresponding cylindrical guide bearings 28;, 29' in the cylindrical frame member 30 attaohed tothebase member ID Withcorresponding coil compression springs 26A, 21A disposed be tween the housing 3t and the respective contact members 24, 25 topress these members inwa fdly against cylindricalmold H,

This mold member ii is dished at its upper-end as; shown in Figure 6' to form a suitable retain;- ing member for the molding material 20 either while in the solid; form or while being heated by; a gas or. acetylene flame. The channel 2,! and Preformed; cavity 22 in the mold ll is pre formed in conventional, manner well known to those shilledhintheart. Of importance, and; the

basis; for the: present application; is hemecha...

includes he cap member which. is moved withgreat. fierce and; with: hang in. the:

tion of mold II. The resulting shock forces developed upon contact of the wet asbestos or "Moldene material l6 within the cap member I2 with the mold I I are absorbed or transmitted to the base member ID through the outer cylindrical metal sheath 23. The other dynamic forces in the moving cap member l2 are transmitted to the base Ill through the frame 30.

The cap member or percussion produced in member I2 is in the form of a cylindrical inverted dish with an inwardly turned annular flange IOA adapted to retain therein the Moldene or asbestos material 16 and carries a hook H113 to facilitate upward manual movement to its cocked position shown in Figure 1 against the action of the tension springs l4, I5. The cap member l2 has extending therefrom the arm 32 with the bearing sleeve 34 formed therein through which the pivot pin 35 passes, the pivot pin 35 having its ends clamped by bolts 37, 33 in the bifurcated extensions 39, 40, respectively, of the base member 36. These bifurcated extensions 39, 40 extend further outwardly and form into a centrally disposed extension 4|.

The coil tension spring I4 has one of its ends attached to the base member extension 4| and the other one of its ends attached to the extension 32 of the pivotally mounted cap member l2; Also mounted on the extension 32 is a pivotally mounted catch member 32A forming a portion of the cocking mechanism.

The spring l has one of its ends mounted on a threaded rod passing through and held in place on the cap member l2 by the knurled adjusting screw 42 which is adjustable to preset the tension in spring IE to a predetermined magnitude. The lower end of the spring is attached to the lever member 44 which is pivo-tally mounted on the pivot pin 45 held in the spaced bracket members 46 on the base member l0. This spring 1 member is attached to the lever member 44 at a point intermediate the pivot pin 45 and the most inward end of the lever member 44 upon which a hook member 49 is fastened to co-operate with the catch member 32A, the other end of the lever member 44 being engageable with the inwardly extending end of the pivotally mounted finger-operated lever member l3. Lever member I3 is pivotally mounted on pivot pin 50 which ,is held in bracket member 52 mounted on the 'base 10.

'Thus, the springs l4, l5 tend to rotate the cap member [2 in the clockwise direction in Figure l and simultaneously the spring 15 tends to rotate the lever member 44 also in the counterclockwise direction in Figure 1 to press the hook member 49 carried thereon into engagement with the cap member 32A mounted on the extension 32 of the cap member l2. This lever member 44 may be rotated counterclockwise against the action of spring [5 to break the connection between the hook member 49 and the catch member 32A by manual operation of the finger-operated lever member l3. In such case it is noted that movement of the finger-operated member I3 is recessed only by the tension in spring l5, "while both springs 14, I5 are effective, once the connection between elements 32A and 49 is broken move the cap member 12 downwardly with position, the spring member 60 being deflected laterally when and as the cap member l2 moves from the position shown in Figure 1 to the position shown in Figure 2 and when the cap is in the latter position returns to engage the top of the cap l2 to firmly press it downwardly.

In order to cock the cap member l2 in its position shown in Figure 1 the spring holding member 66 is first moved outwardly and then the cap member I2 is raised by applying a force to the handle IBB to rotate such cap member about the pin 35. In such upward movement of cap member E2 the springs l4, [5 are tensioned, the catch member 32A slides over the hook 49 and, subsequently, after the manual forces are released the cap member !2 tends to return to its initial position shown in Figure 2 but is prevented from doing so upon engagement with the hook member 59 with the catch member 32A as shown in Figure 1. Thereafter, to release the connection between the hook member 49 and the catch member 32A it is necessary to operate the fingeroperated lever I3.

This finger-operated lever I3 is operated immediately after the molding material 20 is being heated by a gas flame, so that there is substantially no appreciable time interval between the cessation of heating of the molding material 20 and the application of percussion or compression forces to the upper surface thereof, which percussion forces cause the molding material 20 to flow through the channel 2| into the preformed hollow portion 22 of the predetermined shape.

While the particular embodiments of the present invention have been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made without departing from this invention in its broader aspects and, therefore, th aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of this invention.

I claim:

1. A molding device of the character described comprising a base member arranged to releasably hold a mold; a cap member pivotally mounted on said base member and movable in a path to enclose the interior of said mold held in said base and to forc molding material in said mold; a first tension spring having one of its ends connected to said cap member and the other end to said base tending to move said cap member into contact with said mold; a pivoted catch member mounted on said cap member; a first lever member pivoted on said base member having one of its ends engageable with said catch member to maintain said cap member in cocked position; a second tension spring having one of its ends connected to said cap member and the other of its ends connected to said lever member tending to move said cap member into proximity with said mold and pressing said lever member into engagement with said catch member; and a finger-operated lever member on said base member movable to contact and to move said first lever member against the action of said second spring to release the connection between said first lever and said catch.

2. A molding device of the character described in which a cap member is moved under the action of two separate tension springs to enclos the interior of a mold held in a base member, the subcom'oination comprising, a base member; a cocking mechanism comprising a pivoted catch member on said cap member; a first lever member =pivotally mounted on said base member and adapted to engage said catch member, one of said two springs having one of its ends attached to said cap member and the other one of its ends attached to said lever member; and a finger-operated lever pivoted on said base member and movable to contact and to move the first lever against the action of only said one spring to release the connection between said pivoted catch and said first lever member.

3. A molding device of the character described, comprising a base member; a spring-biased contact member arranged to hold a mold firmly with respect to said base; a pivoted cap member mounted on said base; a first tension spring having one of its ends connected to said cap and the other of its ends connected to said base tending to rotate said cap in the direction of the mold, said cap member having mounted thereon a pivoted catch member; a first lever member pivoted on said base member adapted to engage said catch member to maintain said cap member in cocked position; a second tension spring having one of its ends attached to said cap member and the other One of its ends attached to said lever member; and a finger-openated lever pivoted on said base member and movable to contact and to move said first lever against the action of said second spring to break the connection between said first lever and said catch to thereby trip the cap whereby it may move under the influence of both said first and said second springs.

4. In a molding device of the character described, a base member adapted to hold a mold: a cap member pivotally mounted on said base and movable in the direction of said mold; a

pivoted catch member mounted on said cap member; a first lever member pivoted on said base member having one of its ends adapted to re leasably engage said catch member to latch said cap in position; a spring having one of its ends attached to said cap member and the other one of its ends attached to said lever member adapted to move said cap member in the direction of said mold and to press said lever into latching engagement with said catch; and finger-operated means on said base member movable to contact and to move said lever out of engagement with said catch to thereby allow said cap member to move in the direction of said mold under the influence of said spring.

5. The invention defined in the next preceding claim characterized by the fact that there is an adjustable screw threaded extensible connection bet-ween said spring and said cap to provide for adjustment of said spring.

MARIO T. DAVID.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,030,868 Brophy July 2, 1912 1,105,425 Hart July 28, 1914 1,352,080 Montuori Sept. 7, 1920 1,366,875 Collignon Jan. 25, 1921 1,452,246 Marshall Apr. 17, 1923 1,556,239 Mixon Oct. 6, 1925 1,990,862 Forde Feb. 12, 1935 

